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Executing External Commands External Commands

Perl enables you to call external command-line utilities

Whenever possible, avoid calling external commands

• Perl supports a large number of built in functions
• External commands are generally not portable
• Often more time consuming (process setup/teardown overhead)

There are several methods to execute external commands

• The open() function
• The system() function
• Back-quotes
• The fork() & exec() functions

The native shell is used to execute the command line